Analysis Shows Life-Cycle Impacts of Lithium-Ion Batteries

A Chevrolet Volt and replica of the t-shaped battery pack (Photo by John F. Martin for General Motors)

A cradle-to-grave analysis of lithium-ion batteries, like those used in electric vehicles, shows the batteries have potential adverse impacts on the environment and public health beyond the benefits from their day-to-day use. The study, by consulting firm Abt Associates in Bethesda, Maryland, was conducted for the U.S. Environmental Protection Agency, with researchers from battery manufacturers, recyclers, and suppliers, and colleagues from Argonne National Lab (part of Department of Energy), and academic institutions.

The study aimed to identify materials or processes used in the full lifetimes of lithium-ion batteries, from the materials used in manufacturing the batteries through their end-of-life and recycling. The batteries themselves are used to power electric and plug-in hybrid vehicles that reduce or eliminate the use of gasoline. But the analysis highlighted areas for improvement that can reduce the impact of the batteries on the environment and public health.

The researchers assessed three battery cathode chemistries — lithium-manganese oxide, lithium-nickel-cobalt-manganese-oxide, and lithium-iron phosphate — along with battery anodes made with single-walled carbon nanotubes, which are still in development. Batteries made with cathodes using nickel and cobalt, and electrode processing with solvents, have the most potential adverse environmental impact, including resource depletion, climate change, ecological toxicity, and human health, such as respiratory, pulmonary, and neurological effects.

Other environmental and health impacts resulted from the methods used to recharge the batteries, drawing power from conventional electric power plants. Some of this type of impact depends on the location of the power being generated. In the Midwest and South, for example, electric power generally comes from coal-fired plants, while utilities in New England and Calfornia use more renewable sources and natural gas to generate electricity.

The team assessed the impact of single-walled carbon nanotubes because of their ability to improve the energy density and performance of electric vehicle batteries. The researchers found significant energy use in the early stages of carbon nanotube production, which may outweigh the benefits of energy efficiency once the batteries are actually used.

Since batteries with carbon-nanotube anodes are not yet in production, says the team, manufacturers can still refine their production processes to reduce their energy intensity and improve the environmental impact accordingly. The researchers also recommended techniques to reduce the environmental impact of current manufacturing processes, through cathode material substitution, solvent-less electrode processing, and recycling of metals from the batteries.

Read more:

• Quality Check Technique Devised for Lithium-Ion Batteries
• Graphene/Vanadium Oxide Ribbons Boost Battery Storage
• Renewable Power Storage, Management Modules in Development
• ARPA-E to Fund $43 Million for Energy Storage R&D Projects
• Scientists Produce Ultralight Carbon Nanotube Material

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